Question

A white ray of light passing through a prism is dispersed, why? Define angular dispersion

Answer 1

A light ray is refracted (bent) when it passes from one medium to another at an angle and its speed changes. ... Because white light is made up of ALL visible wavelengths, its colors can be separated (dispersed) by this difference in behavior.
Angular dispersion:angular dispersion. noun, Optics. a measure of the angular separation of light rays of different wavelength or color traversing a prism or diffraction grating, equal to the rate of change of the angle of deviation with respect to the change in wavelength.

Answer 2

These colors are often observed as light passes through a triangularprism. Upon passage through theprism, the white light is separated into its component colors - red, orange, yellow, green, blue and violet. The separation of visible light into its different colors is known as dispersion.